汽车底部外形对气动特性的影响  

Influence of Automotive Underbody Shape on Aerodynamic Performance

作　　者：王靖宇[1] 赖晨光[1] 胡兴军[1] 

机构地区：[1]吉林大学汽车工程学院,吉林长春130025

出　　处：《中国公路学报》2008年第2期111-115,共5页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(60222207);吉林大学"九八五"工程项目(200501)

摘　　要：以降低车身阻力和提高汽车的行驶稳定性为目的,对车身底部的流动特性进行数值模拟,以使通过车身底部的流动最佳化。以某轿车的1∶5模型为研究对象,对汽车底部外形进行各种改型设计,研究汽车底部凸凹外形对汽车空气动力特性的影响,并对产生这些影响的原因进行了分析。模拟计算结果表明:汽车底部外形越复杂,气动阻力系数和气动升力系数越大;对气动阻力系数影响最大的是车轮,对气动升力影响最大的是轮腔。计算和分析的结论可为汽车底部外形设计和改型提供参考,也为获得复杂车身底部流动最佳化外形打下了基础。In order to reduce the aerodynamic drag and improve the automotive maneuverability by optimization of automotive underbody flow. The automotive underbody flow characteristics was simulated. Regarded a 20 % scaled car model as research object, different underbody shapes were designed. The influences of the automotive rough underbody shapes on automobile aerodynamic characteristic were researched and the reasons were analyzed. Simulated results show that the coefficients of aerodynamic drag and lift become bigger if the underbody shape is complex. Main influence factors which affect coefficient of aerodynamic drag are wheel, cavity of wheel, vent- pipe groove and shape in turn. Main influence factors which affect coefficient of aerodynamic lift are cavity of wheel and wheel in turn, and the influences of vent-pipe groove and shape are small. Computational results will provide recommendations for automotive underbody shape design and make foundation of continuing to study the automotive underbody flow mechanism and the optimal underbody flow shape.

关 键 词：汽车工程 凸凹外形 数值模拟 底部流动 气动阻力 气动升力 

分 类 号：U461.1[机械工程—车辆工程]